Treatment of printing-plates.



M. A. MGKEE. TREATMENT 0F PRINTING PLATES. APPLICATION FILED MAR. 24, 1911.

Patented Nov. 4, 1913.

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mw NW M. A. MoKEE.

TREATMENT 0T PRINTING PLATBS.

APPLICATION FILED MAR. Z4, 1911. I.

Patented Nom-4,1913.

3 SHEETS-SHEET 2.

M. A. MOKEE. A TREATMENT OP PRINTING PLATES.

APPLICATION FILED MAB.. 24, 1911.

Patented Nov. 4, 1913.

3 SHEETS-SHEET 3.

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MILTON e. Merian, or' wasn-Entr, introns 'ISLAND-.Kassiererin 'ro c.y n. jcrrnn'tr a soNs COMPANY, or New YORK, N. er., .a CORPORATION or NEW aEnslEY.

TREATMENT or riar'NfrrNe-TPLATES.

To a'Z'l whom @it may concern Be it known that I, lVLILToN A. MCKEE, a

citizen of the United States, and residentof Westerly, in the county of Washington and State of Rhode Island, have invented a new and useful Treatment of Printing- Flates, of 'which the following is a specification.

ln the preparation of printing plates after the plate has been cast, its printing face and its back will be more or less distorted and the plate will be liable to be thicker 'at one portion than at another.

rlhe object of this present invention is to treat the plate so that its printing face and its back will be brought into substantial parallelism', thus obviating the necessity of using an underlay during the printing operation, the treatment of the plate also being carried out without'the use of a matrix.

This invention is particularly directed to the process of treating printing plates consisting in subjecting the back of the plate to local pressure along the same in close proximity to a shaving knife as the plate is being subjected to its shaving operation, the plate being placed face down upon'the bed of the shaving machine without an interposed matrix, the said local pressure serving to assist the shaving knife in crowding or forcing themetal away from `the edge pf the knife at the unsupported portions 'of the plate, z'. e., the parts not resting on the,

bed so that when the shaving operation is completed', the plate will be of substantially the same thickness throughout. f

Means for carrying out my process are represented in the accompanying drawings, in which,

Figure l represents a printing plate shaving machine suitable for carrying out my process. Fig. 2 is a top plan view of the machine. F ig..3 is an venlarged detail longitudinal vertical section through the machine, Fig. -4 is an enlarged detail. section taken in the plane of the line A-A of Fig. 5, Fig. 5 is an enlarged vdetailvertical longitudinal section at the shaving knife and springpressed ngers illustrating the action of the knife and fingers with respect to the back ofthe printing plate. Fig. 6 is van enlarged transverse deta-il'secti'on of the inner spring-pressed plate holding roller. Fig. 7 isw an enlarged detail view showing in side elevation the device for adjusting the plate sp'eieanoa of Letters raient;

'Application filed. March 2e, 1911.

` Patented Nev. a, 1era. sei-m1 No. eige-,736.

cramping roller, Fig. 8 is an enlarged sec-l tion taken in the plane ofthe line BI-B of Fig. 7. Fig.. 9 is a transverse section through a portion of a plate before it has been subjected to its shaving operation. Fig. 10 is a transverse sectional View showing the printing plate being subjected to `Vthe action of the shaving knife, Fig. 11 is a transverse section through 'a portion-of the plate after it has been subjected to the A.

is denoted by 1 and .itsreciprocating bed by 2. The bed rack is "denoted by 3 and is driven backward and .forward by a'reversing pinion 4 'mounted on a shaft `5 driven by a worm and gear connection 6, 7, from a drive shaft 8, which shaft in turn is driven lfrom any suitable source ofpower, such, for instance, as a reversing motor' 9, by a belt and pulley connection 10, 11, 12.

The movement of the bed may be reversed automatically and may also be reversed manually by the st-arting and reversing "le.

ver 13. The movement of the bed may-also be controlled by the starting lever 13;` rlhe knife controlling lever is denoted byv 14. These levers are suitably' connected to the parts which they control and asvthey form no 'part of the present invention, 'their operation will not be specically described herein.`v

I T5 The main frame ofthe shaving machine.

The Shaving knife is denoted by 15, and it ijs i adj ustably mounted on `a member 16 which in turn is adjustably mounted upon the frame pressed plate'engaging'roller 18 is mounted in the vertically adjustable` knife carry- Aing member 16. The vertical adjustments of the shaving knife 15 are controlled by a hand wheel-19 having a geared connection 20, 21, 22, with the vertical adjusting screws 23, 24. A micrometer adjustment of the knife carrying member 16 maybe provided by a hand shaft 25 provided witha worm and gear connection 26, 27, with the 17 adjustable in the main frame 1. The spring 190 I these ingerscomp'rises a downwardly and inwardly extended arm 31 and an-upwardly extended arm 32. The arm 31 is provided "with a barreled. roller 33 arranged to roll along the back .of the printing plate 34 in close proximity' to .the spaving. knife .15. A screw bolt 35j extends orwardlyfrom the .uprising arm 32 of eachspring-presse'd tinger,`wh1ch bolt passes through a' cross piece 36 of the brackets 30. A- spring 37 isvinterposed between the cross piece 36 andan adjusting nut 38 on the said screw bolt. An

adjustin -nut 39 on the screwv bolt 35, in front o the cross piece 36, serves to limit the inward movement of the arm 32' of the spring-pressed lingerand thereby the downward ymovement of the arm 31. The tension of the spring 37 may be adjusted by the nut 38. These nuts 38,39, may be provided with lock nuts 40,41, for locking thenuts 38, 39, in their adjusted position. A cramping roller 42 is carried by arms 43 supported upon a cross shaft 44 mountedv eccentrical'ly in bushings 46V rotatably mounted in the -fbrackets 30. Stops 45 on the brackets 30 limit the inward movement of the roller 42.

- This roller 42 serves to hold the printing plate firmly down uponthe bed 2 of the machine as the plate is passed beneath the.

shaving knife 15.

lMeans are provided for adjusting the crampingiroller 42 toward and away from 4.5 the bed 2, which means consists in the present instance, of flanges 47 on the eccentric bushing 46, which flanges have elongated Aslots 48 through which clamping bolts A49 extend for securing the ang'es rigidly-to the brackets 30 atany desired position with-` in the limits of their rotative movements.

In carrying out the process, the printing plate is laid face down on the bed 2 of the shaving machine.

The' back of the plate is then subjected'to the action `of the shaving knife 15. `The plurality of-independent sprung-pressed fingers located adjacent to the knife will exert their pressure upon the back of the plate as it passes beneath the knlfe, thus serving to. exert pressure locally along the plate and assist the knife in.

crowding the unsupported 'parts of the plate, z'. e., the parts not resting on thebed, away from the edge of the knife, thus permitting the thicker portions of 'the plate to be removed therefrom in one or more shavings by the knife. The shaving operation is continued until a lfull shaving 1s made covering the entire area of the back of the` plate, or unt-il the plate has been shaved to lthe desired thickness. In either event, the plate will then be practically of the same thickness throughout.

Ther printing late has a certain amount of resiliency an lence when the various portions of the plate are deiiected or pressed down during the-shaving operation, such deiiect-ions are but temporary and as soon as the pressure is removed, such deiiected portions will spring back to their lnormal position. Therefore it will'be seen that when all of the several shaving operations have been concluded,` the printing face and the back of the'plate willbe substantially. parallel, ever though the plate itself is not absolutely leve.' y

If l.so desired, the plate, after the shaving operation, may be subjected to the action of heat and pressure for leveling the printing face of the plateas represented in Figs. 12 and 13.v

In so far as certain features of my invention -.are concerned, it will be understood that I do not wish to belimited to all of the steps as vdisclosed herein, for some of such steps may be used without the others or in connection with still other steps or modes of treatment,if so desired.

By the -use of the ex ression exerting pressure locally upon the ackrof the plate I Wish to be understood as lcontemplating the independent application ofk ressure at different points upon the back o the plate.

What I claim is:

1. In the process of treating printinfr plates, to bring their `printing faces an backs into substantial parallelism, lacing` the plates `on a ilat surfacle subjectmg the oack or the plate to the action of a shaving knife and. to the independent application of.,

pressure at different points along the same,

in close proximit to the shaving knife, for assisting the knlfe in forcing the unsupf ported parts of the plate away from its edge during the shaving action. j

2. ln ,the process of -treating printing plates, to bring their printing faces and backs into substantial parallelism, placing the plates on a iiat surface, subjecting the back of the plate to the action lof a shaving knife, and to the independent application of pressure at dierent' points along the same, in close proximity to the shaving knife, for

assisting the knife in forcing the unsupv l ported parts of the plate awayfrom its ed e during the sh'aving action, and finally su jecting the plate to heat and pressure for leveling the-face of the` late.

. 3. In the processL o treating printin plates, to bring their printing faces an backs into substantial parallelism, placing the plates on a flat surface, sub'ecting the back of the plate to the action o a shaving knife and to the independent application of pressure at different points along the same, in close proximity to the shaving knife, by a plurality of independent pressure devices, for assisting the knife in forcing the unsupported parts ofthe plate away from its edge during the shaving action.

l:L In the process of treating printing plates, to bring their printing faces an backs into substantial parallelism, placing the plates on a flat surface, subijecting the back of the -plate to the action o a shaving knife and to the independent application of pressure -at' different points along the same,

in close proximity to the shaving knife, by a plurality of independent pressure devices, for assisting the knife in forcing the unsupported parts of the plate away from itsedge during the shaving action, and nally subjecting the plate to heat .and pressure for `leveling the face of the plate.

In testimony, that l claim the foregoing as my invention, I have signed my name, in 25 presence oftWo Witnesses, this twenty-third day of March 1911. e

MILTON A.. MCKEE.

Witnesses:

F. GEORGE BARRY, HENRY C. THIEME. 

